What are parts of the nervous system? Flashcards
Parts of the Vascular System - Blood Supply
-Carotid arteries
-Circle of Willis
-The Blood Brain Barrier
Cartoid arteries
the major arteries to the brain
Circle of Willis
a structure formed by the major cerebral srteries
Blood Brain Barrier
the result of higher resistance in brain capillaries that restricts the passage of large molecules - the endothelial cells lining the blood vessels are tightly bound
Hemorrhagic Stroke
occurs when a rupture in an artery allows blood to leak into the brain
Ischemic Stroke
clots or other debris prevent blood from reaching a region of the brain, causing it to die
Meninges
-Dura Mater (top layer)
-Arachnoid Mater (middle layer)
-Pia Mater (Inner layer)
Subarachnoid Space
-filled with CSF
-the fluid-filled sac surrounding the brain helps to prevent the brain from
Ependymal Cells
-Line the meninges (wrappers surrounding
the nervous system)
-Form lining of ventricles
(fluid-filled spaces of the nervous system) – ependymal cells
-Secrete cerebrospinal fluid
Choroid Plexus
-a membrane lining the ventricles that produces cerebrospinal fluid
Nervous System Anatomy
-the nervous system is highly organized
-this is true at all levels - gross anatomy (that which you can see by eye) to the microscopic level
-the “parts” are important to us because structure = function in the nervous system
-concept of modularity
Directional and Planar Labels
-Horizontal plane: rostral (anterier) to caudal (posterior) cut
-Sagital plane: dorsal to ventral cut Cut the middle of the brain (seperate right and left)
-Coronal plane: dorsal to ventral cut (crown) (face vs back of head)
Direction & Flexure
-Anterior –> posterior: head vs feet
-Dorsal –> Ventral: back vs front of the body
-Rostral –> Caudal: front of the brain to the back of the brain
-Medial –> Lateral: middle of the body to the outside of the body
-Ipsilateral –> Contralateral: same side of the body vs opposite side of the body
-Distal –> Proximal: far vs close
Peripheral Nervous System
all parts of the nervous system found outside the skull and the spinal column
Central Nervous System
brain and spinal cord
Autonomic nervous System
-Part of the PNS
-Involuntary
-Consists of many ganglia (bundles of neurons) distributed all over the body that somewhat independently influence visceral organs
–Sympathetic (fight or flight) (Norepinephrine)
–Parasympathetic (relax) (Acetylcholine)
–Enteric (gut/digestive control)
Somatic Nervous System
-Part of the PNS
-Voluntary
-Nerves from your sense organs
back to the CNS to feed your brain
information about what is going on
around your body
-Consists of nerves from the CNS to
the skeletal muscles allowing you to
move your body willingly
-nerves include axons traveling to the CNS from the ears, eyes, skin, tongue, nose, muscles, tendons, etc.
Central Nervous System (details)
-Spinal cord (tail/caudal) to brain (nose/rostral)
-Responsible for:
–Senses: sight (vision), hearing (audition), smell (olfaction), touch, taste
–Initiating movement of your muscles
–Attention, cognition, perception, thought, affect, mood
-Also responsible for other automatic life-essential function
–Breathing, hunger regulation, thermoregulation, pain regulation, circadian rhythm
-As you move from tail (caudal) to nose (rostral) of the CNS, functions carried out generally become less automatic and more complex
Parts of the Brain CNS
-Cerebral cortex
-Basal Ganglia
-Thalamus
-Hypothalamus
-Brain stem (midbrain, pons, medulla)
-Cerebellum
Parts of the Spinal Cord CNS
-Cervical (Neck)
-Thoracic (trunk)
-Lumbar (lower back)
-Sacral (pelvic)
-Coccygeal (bottom/tail bone)
Dorsal Root Ganglion
take informationmfrom the skin to the spinal cord; sensory
Ventral Root Ganglion
cell bodies are in the ventral horn and send axons to the effector muscles; make the muscle move; motor
Sulcus
a groove in the cerebral cortex
Gyrus
matter between two grooves/wrinkles
Evolutionary trends
-the most complex behaviors an organism can do, the larger the brain is
Gray Matter in the brain
contains cell bodies and dendrites, which lack myelin
White matter in the brain
consists of axons with white myelin sheath
Axon Tracts
-When lots of myelinated axons travel together, they appear white
-Multiple axons traveling together form a tract
-Cortical and subcortical regions communicate
with one another via these tracts
-Corpus collosum
Corpus Collosum
axon tract that joins the two hemispheres
The lobes of the cerebral cortex
-frontal lobe
-parietal lobe
-temporal lobe
-occipital lobe
Cerebral Cortex
divided into sensory, motor, and associative processing areas
Sensory Processing Areas
-involved in processing sensory input. Receive strong input from sensory organs
–Primary sensory cortex
–Visual cortex
–Auditory cortex
Motor Processing Areas
-involved in driving movements or generating motor responses. Makes strong connection to the spinal cord
–Primary motor cortex
Associative Processing Areas
-involved in cognitive operations that are intermediate between sensing
stimuli and acting upon them
–Parietal lobe
–Temporal lobe
–Prefrontal cortex
Associative Processing Areas
-involved in cognitive operations that are intermediate between sensing
stimuli and acting upon them
–Parietal lobe
–Temporal lobe
–Prefrontal cortex
Homunculus
-Primary Motor Cortex: in front of the central sulcus
-Primary Sensory Cortex: behind the central sulcus
Functional Neuroanatomy
-The cerebral cortex is made up of many
different sub-regions that have distinct
functions but have surprisingly similar
structure (cytoarchitecture)
-Cortical regions are largely defined by
what they are connected with and their
sub-regional cellular architecture
Six Layers of the Cortex
-Cortical regions generally have six layers
-Layers 5 and 6 consist of pyramidal cells
= cells bodies of pyramidal neurons reside
here –> major output layers
-Apical (top) and basal (bottom) dendrites
receive information from layer 4 major
input layer
-Pyramidal neurons are projection cells
– project information to other cortical
and subcortical areas
Internal Systems and Subcortical Regions
-Thalamus
-Hypothalamus & Pituitary Gland
-Cingulate Gyrus
-Amygdala
-Hippocampus
-Stria Terminalis
-Caudate
-Substantia Nigra
Thalamus
major relay station for sensory information coming into cerebral cortex
Hypothalamus & Pituitary Gland
neurohormone center, biological rhythms, hunger/thirst, body temperature, sexual drive
Cingulate Gyrus
attention
Amygdala
fear processing, appetitive behavior, emotion “center”
Hippocampus
learning and memory formtion
Stria Terminalis
sex and threat responses; integration of hormonal signals; basal part of the stria terminalis is involved in appetitive behavior and emotion regulation
Caudate
habit formation
Substantia Nigra
consists of cell bodies of neurons that produce the neurotransmitter dopamine. Involved in
movement continuation
Brainstem
-Midbrain, pons medulla
-Axons coming and going between spinal
cord and brain
-Controls head, eyes, gaze
-Autonomic / automatic functions
-Superior Colliculus
-Inferior Colliculus
Superior Colliculius
visual information processing – particularly, processes gaze information
Inferior Colliculus
auditory information processing
Pons
attached to the cerebellum and contains motor control and sensory nuclei; gives rise to the cranial nerves
Medulla
-contains cranial nerve nuclei and marks the transition from brain to spinal cord
–Involved in breathing and heartrate
regulation
Cranial Nerves
-Bundles of axons
-Within a nerve, different
axons control sensory
and motor processing
Cerebellum
-Fine motor control
-Gait, balance
-Muscle coordination